Lighting fixture



Nov. 15 w a s. B. KRAUT El AL I 3 LIGHTING FIXTURE Filed March 8, 1935 2 Sheets-Sheet l NVENTORS WITNESS s; I @w/CM Samuel B. Krauf &

' Har @[Ofmuse WW ing lateral and vertical distribution of thelight Patented Nov. 15, 1938 5 PATENT. oFFi-eE LIGHTING FIXTURE Samuel B. Kraut and. Harry J. Chase, Lakewood, Ohio, 'assignors to Westinghouse Electric & Manufacturing Company. East Pittsburgh, Pa.,

Our invention relates, generally, to lighting fixtures; andmore particularly,.to street orhigh-' .way lighting units adapted to" project: beams of light in opposite directions; along the street or highway.

Theobject. of our invent1on generally stated is to" provide a street or highway lighting. unit of ornamental nature whichshall-beefficient in operation and economical to manufacture, install and maintain.

A more specific object of our inventionis' to provide for obtaining a predetermined? light dis.- tribution from a light source by means of a plurality of reflectors combined. as a unitary structure:

' Another-object of our invention is to provide for utilizinga plurality of horizontally and vertically disposed reflecting mediums to: produce an asymmetric or other predetermined light distribution;

A still further object of the invention is to .provide'for. obtaining an asymmetric light distribution for street and highway illumination by means of a; plurality of: curved reflectors arranged in a predetermined manner with respect to one anotherandthe light source and combined into-a unitary structure.

' Other objects and advantages of our invention will becomeevident from a reading of the following detailed description in conjunction-with the drawings inwhich:

Figure 1 is a. top plan-view of the unit embody.- ingthe-principal features of the: invention showing the shape of the upper housing. Fig. 2 isa view partly in elevation and partly insection showing the shape of and position of the horizontalreflectors,

. .Fig- 3 is an end elevational view of the unit showing'theshape of the-vertical reflectors and their relative positions with respect torthe light source,

Fig. 4 is another end'elevational view partly insection throughlines IV--IV of Fig. 2,,showing the position of the-light source and its socket, and

Figs. 5 and 6 are views of typical curves showproduced by theparticular unit. illustrated.

Referringdnow' to Figs. 1 through 4- of the drawings, it will be observed. that the lighting unit comprises a main or upper'housing member l0 which functions as a protective top aswell as a supporting means for the light source H which is illustrated in this instance as a sodium lamp. It is to be understood, however, that the use of a unit of this general type is not limited to any'particulartypeiof lamp as sodium, mer

cury, incandesc'ent or'any other suitable type of lamp may be used to equal advantage as will be referred to hereinafter.

a corporationof Pennsylvania Application; March 8, 1935, Serial No. 9, 99:' 6 Claims. .(Cl; 240-25) "As shownlbest in Figs; 2 and 4, the housing i0 is provided with a central dome-shaped portion t2 whichiisprovided with athreaded-opening, l3 at the top thereof to receive a supporting member whereby the" unit maybe supported above the street or other surface'to be illuminated. The light source ll? may be supported-in; a vertical position from the housing, It by: means ofa=suit ablesocket M, which may be placed within the dome-shapediportion t2 and secured to-thehousing; inany suitable; manner asshown: in Fig. 4. In this instance; the light source: II is provided with-a flask l5 which-maybe supported by means of a clamp I'Gor inwany; other suitable manner.

Irr order to control the light. distribution of the source Ha pluralityof reflectors areutilized which may be'referred to as -horizontal and'zvertical reflectors.- .The' horizontal reflector I1- is mounted on the underneath side of the housing member-"I0 and-may be secured thereto in any suitable manner such for example, as by'means 'oithe-studs l8* and screws IB: The horizontal and curved as to give the desired light. distribution, In. this instance the two upper or horizontal: reflectors I1 are curved to the same degree and? are identical in shape, flaring out.- wardly as viewed from. the top or. bottom, from the central portion ofthe unit near: the light source I I I The. vertically disposed reflectors 2t and 22 may: likewise bein one or two pieces and supported fromv the. housing l0 by means of depending supporting arms 23 whichmay or may not be formed/integralIWith the housing 1 0;. The vertical reflectors maybe secured to-thearms-23 by screws-24 as shownin Fig. 2.

1 As in the case 01- the horizontal reflectors I! the vertical reflectors 2| and 22v are so shaped and-curvedasto produce the desired-form oflight distribution. The unit illustrated is particularly adapted for. street or highway lighting and as viewed in Fig. 3 the left sideis: the street side as to produce an asymmetric light distribution as shownin'Figs. 5 ;and 6 which are typicallight distribution-curves for the particular embodiment of the invention illustrated. Fig. 5' shows the lateral distribution-of? light while Fig. 6 illustrates the .vertical distribution, the beams being shown ."ass'directed approximately 160 degreeszapart horizontal and: 15 degrees below the vertical.

Itwill be readily understood that almost any form of light distribution may be obtained by varying the shape and curvature of certain ones or all of the reflectors to obtain the desired results. Further, the use of different kinds of lamps or light sources may require changes in the shape and curvature of the reflectors in order to obtain the exact form of light distribution desired, but, in general, the shape and curvature of the reflectors is somewhat the same for all of the different types of lamps for any particular form of light distribution, such, for example, as asymmetric distribution as shown.

The reflectors may be made of any suitable material, although we have found that sheet aluminum properly treated to produce a good reflecting surface is a very good material for this purpose as it is easily formed and rust and corrosion resistant.

In view of the fact that the reflectors are so positioned as to obtain the greatest degree of protection, there is' a minimum possibility for the accumulation of dust and dirt which causes the unit to function at a high efiiciency with a minimum of maintenance.

The great simplicity of the design produces a decorative type of unit and at the same time makes it possible to easily service and maintain the unit as it may be relamped without removing a heavy globe or the reflectors may be cleaned by simply wiping them ofi.

' In view of the foregoing description, it is evident that we have provided a lighting unit or fixture 'for street or highway lighting which produces a highly uniform and efiicient light distribution, although of simple construction and economical to build and which is equally decorative both day and night,

It may be stated in conclusion, that, while the illustrated example constitutes a practical embodiment of our invention, we do not wish to limit ourselves strictly to the exact details herein illustrated, since modifications of the same may be made without departing from the spirit of the invention, as defined by the appended claims.

-' We claim as our invention:

1'. A lighting fixture comprising in combination, a housing having a dome-shaped central portion and oppositely disposed wing portions, a lamp, a socket mounted within the dome-shaped central portion of the housing for supporting the .lamp in a vertical position beneath the housing,

a plurality of reflector plates supported by the main housing in vertical relation thereto andon opposite sides of the lamp, said reflector plates extending along the edges of the wing portions, and reflector plate means disposed in a substantially horizontal position underneath the wing portions of the housing above the lamp and in abutting relation to the upper edges'of the said vertically disposed reflector plates.

2. In a street lighting fixture, in combination, an elongated housing having oppositely disposed wing portions, a lamp supported beneath the central part of the housing in a vertical position, elongated longitudinally-curved metallic reflector plate means mounted beneath the housing and above the lamp in a substantially horizontal position and having an opening therein through which the lamp extends, and elongatedlongitudinallycurved metallic reflector plate means supported from the housing in a substantially vertical position on two opposite sides of the lamp and extending along and in abutting relation to the sides of said horizontally mounted elongated reflector plate means to provide joined horizontal and vertical reflecting surfaces above and on two opposite sides of the lamp, thereby to distribute light on a roadway in opposite directions.

3. A lighting fixture comprising in combination, a housing member provided with oppositely disposed wing portions having supporting arms depending downwardly therefrom in a vertical position, a lamp supported in a vertical position beneath the housing and centrally thereof, an elongated reflector plate means secured to the housing above the lamp in a substantially horizontal position, and additional reflector plate means secured to the supporting arms on opposite sides of the lamp in a substantially vertical position, the upper edges of the said vertical reflector plate means being disposed in abutting relation to the side edges of'the said horizontal reflector plate means.

4. A lighting unit comprising an elongated housing having oppositely disposed wing members, a socket secured to the housing for supporting a lamp in a vertical position beneath and centrally of the housing, a pair of symmetrically shaped curved upper reflector plates secured to the underside of the housing above the lamp in end-toend relation, a plurality of support arms along the opposite sides of the housing and extending vertically downward therefrom, and a pair of symmetrically shaped curved side reflector plates secured in end-to-end relation to the support arms along the opposite sides of the housing in abutting relation to the upper reflector plates.

5. In a street lighting fixture for lighting the roadway surface in opposite directions beneath the fixture, the combination of an elongated lamp mounted vertically, aluminum reflector plate means having oppositely disposed wing-shaped portions mounted horizontally above the lamp to direct light downwardly and having an opening through which the lamp extends, and a curved aluminum reflector plate means mounted vertically on two opposite sides of the lamp, the curvature of the said vertically disposed reflector plate means generally conforming to the shape of the longitudinal edges of the wing-shaped refiector plate means, thereby to provide a con tinuous reflecting surface above and on two opposite sides only of the lamp.

6. In a street lighting fixture, in combination,

an elongated housing having oppositely disposed wing members a lamp supported beneath and centrally of the housing in a vertical position, an upper reflecting surface above the lamp comprising a pair of wing-shaped reflector plates supported by the housing in end-to-end relation and having their abutting ends curved downwardly and joining in a plane coincident with the longitudinal axis of the lamp, and a vertical reflecting surface on two opposite sides of the supported in a vertical position from the housing in end-to-end relation and curved to conform to the shape of the wing-shaped reflector plates, said vertically-mounted reflector plates having their upperedges in abutting relation to the wingshaped reflector plates, thereby to provide reflecting surfaces above and on two opposite sides of the lamp to direct light therefrom upon the roadway in opposite directions.

SAMUEL B. ImAUT. HARRY J. CHASE.

60 lamp each comprising a pair of reflector plates 

